Respuesta :
Answer:
412.1kJ
Explanation:
For the reaction , from the question -
4Fe (s) + 3O₂ (g) → 2Fe₂O₃ (s)
Δ Hrxn = Δ H°f (products) - Δ H°f (reactants)
In case the compound is in its standard state , enthalphy of formation is zero
Hence ,
for the above reaction ,
ΔHrxn =( 2 * Δ H° (Fe₂O₃ )) - [ ( 4 *Δ H° Fe ) + (3 * Δ H° O₂ )]
The value for Δ H°(Fe₂O₃ ) = - 824.2kJ/mol
Δ H° Fe = 0
Δ H° O₂ = 0
Putting in the above equation ,
ΔH rxn = ( 2 * Δ H° (Fe₂O₃ )) - 0
ΔHrxn = 2× - 824.2 kJ / mol = - 1648.4 kJ/mol
- 1648.4 kJ/mol , this much heat is released by the buring of 4 mol of Fe.
Hence ,
for 1 mol of Fe ,
- 1648.4 kJ/mol / 4 = 412.1kJ
412.1 kilojoules of heat will be released when exactly 1 mole of iron, Fe, is burned to form Fe₂O₃ at standard state condition.
How we calculate the heat released during a chemical reaction?
This heat enthalpy of a reaction can be calculated as follow:
ΔH = ΔHₙ - ΔHₓ, where
ΔHₙ = change in enthalpy of reactants
ΔHₓ = change in enthalpy of products
Given reaction can be represented as:
4Fe + 3O₂ → 2Fe₂O₃
From the above expression it is clear that 4 mole of Fe is burned to form 2 mole of Fe₂O₃.
In the standard condition, heat of formation of pure solid elements is zero. i.e. heat of formation of iron and oxygen = 0.
Heat of formation of Fe₂O₃ at standard state = -824.2 kJ/mol.
Now putting all these values in the above equation, we get
ΔH = 2 × (-824.2) - 0 = -1648.4 kJ/mol
So, 4 mole of Fe released = -1648.4 kJ/mol amount of heat to form Fe₂O₃
1 mole of Fe released = -1648.4/4 kJ/mol amount of heat to form Fe₂O₃
Hence, 412.1 kJ/mol amount of heat to form Fe₂O₃.
To know more about heat released or enthalpy, visit below link:
https://brainly.com/question/14047927
